slot nozzles are employed, e.g., in hot glue guns, by which fusion adhesive fed to them in solid form is melted and applied uniformly to an area which is to be coated, e.g., an edge strip. One slot nozzle of this type is shown in DE-GM 89 07 752.0. In the case of this nozzle an outlet region formed in the shape of a slot is arranged at right angles to the direction of application so that the fluid may be applied in the form of a stripe the width of which corresponds with the length of the slot. Certainly these so-called wide slot-nozzles may readily be used for numerous applications such as, e.g., the coating of edge strips in continuous operation because here the fluctuation in thickness of the applied layer which arises upon interruption of the feed of adhesive, plays no part because of the continuous operation. But there are also cases in which in operation with interruptions in the feed of adhesive the main thing is that the thickness of application of the adhesive shall remain as constant as possible over the whole area to be coated. Such a case arises, e.g., in gluing the backs of books, because the present wide slot-nozzles are less suited to this application. That is, in gluing the backs of a number of books in succession with the necessity of interruption in the application between every two books, problems arise in particular through adhesive keeping on oozing out (intermittent operation).